Improved Sensitivity (improved + sensitivity)

Distribution by Scientific Domains


Selected Abstracts


Improved sensitivity for detecting micrometastases in pelvic lymph nodes by real-time reverse transcriptase polymerase chain reaction (RT-PCR) compared with conventional RT-PCR in patients with clinically localized prostate cancer undergoing radical prostatectomy

BJU INTERNATIONAL, Issue 8 2009
Tomoaki Terakawa
OBJECTIVE To compare the usefulness between real-time reverse transcriptase polymerase chain reaction (RT-PCR) with that of conventional RT-PCR for detecting micrometastases in pelvic lymph nodes (PLN) dissected during radical prostatectomy (RP) for prostate cancer. PATIENTS AND METHODS In all, 120 patients with clinically localized prostate cancer who underwent RP and pelvic lymphadenectomy were included. Expression of prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) in 2215 PLNs obtained from these 120 patients were assessed by fully quantitative real-time RT-PCR and as well as conventional RT-PCR. Specimens, in which either PSA or PSMA mRNA was positive, were regarded as showing the ,presence of micrometastasis'. RESULTS Pathological examinations detected tumour cells in 29 PLNs from 11 patients, while real-time RT-PCR and conventional RT-PCR further identified micrometastasis in 143 and 81 PLNs from 32 and 19 patients, respectively, with no pathological evidence of nodal involvement; that is, the sensitivity of real-time RT-PCR for detecting micrometastases was significantly higher than that of conventional RT-PCR. In this series, biochemical recurrence occurred in 32 patients, and in both assays, there were significant differences in biochemical recurrence-free survival between patients with and with no micrometastases. However, despite the significant association of micrometastases detected by both assays with biochemical recurrence on univariate analysis, the presence of micrometastases detected by real-time RT-PCR but not that detected by conventional RT-PCR appeared to be useful as an independent predictor on multivariate analysis. CONCLUSIONS Although micrometastatic tumour foci in PLNs that were missed by routine pathological examination could be diagnosed by both real-time RT-PCR and conventional RT-PCR assays, it would be strongly recommended to use real-time RT-PCR to detect micrometastases considering its high sensitivity and the close association between the outcome of this assay and the probability of biochemical recurrence. [source]


Electrochemically Functionalized Single-Walled Carbon Nanotube Gas Sensor

ELECTROANALYSIS, Issue 12 2006
Ting Zhang
Abstract We demonstrate a facile fabrication method to make chemical gas sensors using single-walled carbon nanotubes (SWNT) electrochemically functionalized with polyaniline (PANI). The potential advantage of this method is to enable targeted functionalization with different materials to allow for creation of high-density individually addressable nanosensor arrays. PANI-SWNT network based sensors were tested for on-line monitoring of ammonia gas. The results show a superior sensitivity of 2.44% ,R/R per ppmv NH3 (which is more than 60 times higher than intrinsic SWNT based sensors), a detection limit as low as 50,ppbv, and good reproducibility upon repeated exposure to 10,ppmv NH3. The typical response time of the sensors at room temperature is on the order of minutes and the recovery time is a few hours. Higher sensitivities were observed at lower temperatures. These results indicate that electrochemical functionalization of SWNTs provides a promising new method of creating highly advanced nanosensors with improved sensitivity, detection limit, and reproducibility. [source]


Multifunctional Dendrimer-Templated Antibody Presentation on Biosensor Surfaces for Improved Biomarker Detection

ADVANCED FUNCTIONAL MATERIALS, Issue 3 2010
Hye Jung Han
Abstract Dendrimers, with their well-defined globular shape and high density of functional groups, are ideal nanoscale materials for templating sensor surfaces. This work exploits dendrimers as a versatile platform for capturing biomarkers with improved sensitivity and specificity. The synthesis, characterization, fabrication, and functional validation of the dendrimer-based assay platform are described. Bifunctional hydroxyl/thiol-functionalized G4-polyamidoamine (PAMAM) dendrimer is synthesized and immobilized on the polyethylene-glycol (PEG)-functionalized assay plate by coupling PEG-maleimide and dendrimer thiol groups. Simultaneously, part of the dendrimer thiol groups are converted to hydrazide functionalities. The resulting dendrimer-modified surface is coupled to the capture antibody in the Fc region of the oxidized antibody. This preserves the orientation flexibility of the antigen binding region (Fv) of the antibody. To validate the approach, the fabricated plates are further used as a solid phase for developing a sandwich-type enzyme-linked immunosorbent assay (ELISA) to detect IL-6 and IL-1,, important biomarkers for early stages of chorioamnionitis. The dendrimer-modified plate provides assays with significantly enhanced sensitivity, lower nonspecific adsorption, and a detection limit of 0.13,pg,mL,1 for IL-6 luminol detection and 1.15,pg,mL,1 for IL-1, TMB detection, which are significantly better than those for the traditional ELISA. The assays were validated in human serum samples from a normal (nonpregnant) woman and pregnant women with pyelonephritis. The specificity and the improved sensitivity of the dendrimer-based capture strategy could have significant implications for the detection of a wide range of cytokines and biomarkers since the capture strategy could be applied to multiplex microbead assays, conductometric immunosensors, and field-effect biosensors. [source]


Myocardial perfusion imaging in evaluation of undiagnosed acute chest pain

INTERNAL MEDICINE JOURNAL, Issue 9 2001
J. C. Knott
Abstract Myocardial perfusion imaging is a relatively new technique in the emergency department management of acute chest pain. With improved sensitivity and specificity compared to traditional methods of risk stratification, an abnormal scan rapidly identifies individuals with acute perfusion abnormalities and allows the appropriate utilization of limited resources. Conversely, a normal scan allows prompt hospital discharge and is associated with excellent outcomes both in the short and medium terms. Acute chest pain myocardial perfusion imaging has been demonstrated to alter patient management and disposition and its routine use results in decreased costs in the intermediate risk population. (Intern Med J 2001; 31: 544,546) [source]


Identification of novel DNA methylation markers in cervical cancer,

INTERNATIONAL JOURNAL OF CANCER, Issue 1 2008
Hung-Cheng Lai
Abstract Testing for DNA methylation has potential in cancer screening. Most previous studies of DNA methylation in cervical cancer used a candidate gene approach. The aim our study was to identify novel genes that are methylated in cervical cancers and to test their potential in clinical applications. We did a differential methylation hybridization using a CpG island (CGI) microarray containing 8640 CGI tags to uncover methylated genes in squamous cell carcinomas (SCC) of the uterine cervix. Pooled DNA from cancer tissues and normal cervical swabs were used for comparison. Methylation-specific polymerase chain reaction, bisulfite sequencing and reverse transcription polymerase chain reaction were used to confirm the methylation status in cell lines, normal cervices (n = 45), low-grade lesions (n = 45), high-grade lesions (HSIL; n = 58) and invasive squamous cell carcinomas (SCC; n = 22 from swabs and n = 109 from tissues). Human papillomavirus (HPV) was detected using reverse line blots. We reported 6 genes (SOX1, PAX1, LMX1A, NKX6-1, WT1 and ONECUT1) more frequently methylated in SCC tissues (81.5, 94.4, 89.9, 80.4, 77.8 and 20.4%, respectively) than in their normal controls (2.2, 0, 6.7, 11.9, 11.1 and 0%, respectively; p < 0.0001). Parallel testing of HPV and PAX1 methylation in cervical swabs confers an improved sensitivity than HPV testing alone (80% vs. 66%) without compromising specificity (63% vs. 64%) for HSIL/SCC. Testing PAX1 methylation marker alone, the specificity for HSIL/SCC is 99%. The analysis of these novel DNA methylations may be a promising approach for the screening of cervical cancers. © 2008 Wiley-Liss, Inc. [source]


Evaluation of novel fluorogenic substrates for the detection of glycosidases in Escherichia coli and enterococci

JOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2006
J.D. Perry
Abstract Aims:, Enzyme substrates based on 4-methylumbelliferone are widely used for the detection of Escherichia coli and enterococci in water, by detection of , -glucuronidase and , -glucosidase activity respectively. This study aimed to synthesize and evaluate novel umbelliferone-based substrates with improved sensitivity for these two enzymes. Methods and Results:, A novel , -glucuronide derivative based on 6-chloro-4-methylumbelliferone (CMUG) was synthesized and compared with 4-methylumbelliferyl- , - d -glucuronide (MUG) using 42 strains of E. coli in a modified membrane lauryl sulfate broth. Over 7 h of incubation, the fluorescence generated from the hydrolysis of CMUG by E. coli was over twice that from MUG, and all of the 38 glucuronidase-positive strains generated a higher fluorescence with CMUG compared with MUG. Neither substrate caused inhibition of bacterial growth in any of the tested strains. Four , -glucosidase substrates were also synthesized and evaluated in comparison with 4-methylumbelliferyl- , - d -glucoside (MU-GLU) using 42 strains of enterococci in glucose azide broth. The four substrates comprised , -glucoside derivatives of umbelliferone-3-carboxylic acid and its methyl, ethyl and benzyl esters. Glucosides of the methyl, ethyl and benzyl esters of umbelliferone-3-carboxylic acid, were found to be superior to MU-GLU for the detection of enterococci, especially after 18 h of incubation, while umbelliferone-3-carboxylic acid- , - d -glucoside was inferior. However, the variability in detectable , -glucosidase activity among the different strains of enterococci in short-term assays using the three carboxylate esters (7 h incubation) may compromise their use for rapid detection and enumeration of these faecal indicator bacteria. Conclusions:, The , -glucuronidase substrate CMUG appears to be a more promising detection system than the various , -glucosidase substrates tested. Significance and Impact of the Study:, The novel substrate CMUG showed enhanced sensitivity for the detection of , -glucuronidase-producing bacteria such as E. coli, with a clear potential for application in rapid assays for the detection of this indicator organism in natural water and other environmental samples. [source]


Standardization of line-scan NIR imaging systems

JOURNAL OF CHEMOMETRICS, Issue 3-4 2007
Zheng Liu
Abstract A simple and easy to use method is proposed for standardizing NIR imaging systems for differences among detectors in the charge-coupled device (CCD) array and illumination unevenness. The standardization equations are then used to pre-treat NIR image data to reduce the systematic errors introduced by a line-scan NIR imaging system. The method requires only easily available homogeneous standards with relatively uniform spectral response. The effectiveness of the standardization in reducing the pixel-to-pixel biases and other systematic effects is illustrated with examples, and the improved sensitivity in results obtained from a multivariate image analysis (MIA) based on multi-way principal component analysis (MPCA) is demonstrated. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Detection of carcinomas in an asymptomatic Chinese population: advantage of screening with multiple tumor markers

JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2006
Kuo-Chien Tsao
Abstract A total of 73,443 asymptomatic individuals were screened on a voluntary basis for cancer at Chang Gung Memorial Hospital in Taiwan using a panel of tumor markers, including alpha fetoprotein (AFP), CA 125, CA 15-3, CA 19-9, carcinoembryonic antigen (CEA), prostate specific antigen (PSA), chromogranin A (CgA), and squamous cell specific antigen (SCC). The results are derived from data collected from January 1998 to October 2003. A total of 210 cancers (approximately 0.3%) were detected, including cancers of the liver, lung, colon, prostate, stomach, pancreas, breast, cervix, ovary, and bladder. Of the tumor markers monitored, elevated CA 19-9, CEA, and CA 125 were the most frequently detected in a variety of cancers. It was surprising to find that many cancers were not detected by their dominant markers but by the elevation of tumor markers not recommended for monitoring their tumor activity. Screening with multiple circulating tumor markers provides improved sensitivity for cancer detection in asymptomatic individuals before they reach the fatal advanced stage. Screening with multiple tumor markers also allows cancers to be detected in the absence of their dominant markers. If we had not measured the multiple tumor markers, these cancers would have gone undetected. J. Clin. Lab. Anal. 20:42,46, 2006. © 2006 Wiley-Liss, Inc. [source]


Modulation of white adipose tissue proteome by aging and calorie restriction

AGING CELL, Issue 5 2010
Adamo Valle
Summary Aging is associated with an accrual of body fat, progressive development of insulin resistance and other obesity comorbidities that contribute to decrease life span. Caloric restriction (CR), which primarily affects energy stores in adipose tissue, is known to extend life span and retard the aging process in animal models. In this study, a proteomic approach combining 2-DE and MS was used to identify proteins modulated by aging and CR in rat white adipose tissue proteome. Proteomic analysis revealed 133 differentially expressed spots, 57 of which were unambiguously identified by MS. Although CR opposed part of the age-associated protein expression patterns, many effects of CR were on proteins unaltered by age, suggesting that the effects of CR on adipose tissue are only weakly related to those of aging. Particularly, CR and aging altered glucose, intermediate and lipid metabolism, with CR enhancing the expression of enzymes involved in oxalacetate and NADPH production, lipid biosynthesis and lipolysis. Consistently, insulin-, and ,3-adrenergic receptors were also increased by CR, which denotes improved sensitivity to lipogenic/lipolytic stimuli. Other beneficial outcomes of CR were an improvement in oxidative stress, preventing the age-associated decrease in several antioxidant enzymes. Proteins involved in cytoskeleton, iron storage, energy metabolism and several proteins with novel or unknown functions in adipose tissue were also modulated by age and/or CR. Such orchestrated changes in expression of multiple proteins provide insights into the mechanism underlying CR effects, ultimately allowing the discovery of new markers of aging and targets for the development of CR-mimetics. [source]


Five-port receiver with improved sensitivity

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2008
Fernando Rangel de Sousa
Abstract This article reports the architecture of a five-port receiver without vector base circuit generators in which three antennas provide three phase-shifted copies of the received signal. A 2.4-GHz prototype was implemented for concept proofing, and the measurements point to a sensitivity improvement of 6 dB with respect to comparable classic five-port receivers. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2945,2947, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23858 [source]


High-throughput quantification of selenium in individual serum proteins from a healthy human population using HPLC on-line with isotope dilution inductively coupled plasma-MS

PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 19 2010
Sophia Letsiou
Abstract In this study, a method, based on dual column affinity chromatography hyphenated to isotope dilution inductively coupled plasma,quadrupole MS, was developed for selenium determination in selenoprotein P, glutathione peroxidase, and selenoalbumin in human serum samples from a group of healthy volunteers (n=399). Method improvement was achieved using methanol-enhanced isotope dilution which resulted in improved sensitivity and removal of isobaric interferences. Although no human serum reference materials are currently certified for their selenium species levels, method development was conducted using human serum reference material BCR 637 and 639 as their Se species content has been reported in the previous studies, and thus comparisons were possible. The mean selenium concentrations determined for the 399 healthy volunteer serum samples were 23±10,ng Se mL,1 for glutathione peroxidase, 49±15,ng Se mL,1 for selenoprotein P and 11±4,ng Se mL,1 for selenoalbumin. These values are found to be in close agreement with published values for a limited number of healthy volunteer samples, and to establish baseline Se levels in serum proteins for an apparently healthy group of individuals, thus allowing for subsequent comparisons with respective values determined for groups of individuals with selenium related health issues, as well as assist in the discovery of potential selenium biomarkers. Also, the relationship between Se serum protein levels and some anthropometric characteristics of the volunteer population were investigated. Additionally, further development of the analytical method used in this study was achieved by adding a size exclusion chromatography column after the two affinity columns via a switching valve. This allowed for the separation of small selenium-containing molecules from glutathione peroxidase and thus enhanced the overall confidence in its identification. [source]


Serially coupled microcolumn reversed phase liquid chromatography for shotgun proteomic analysis

PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 7 2009
Dingyin Tao
Abstract Microcolumn RPLC (,RPLC) is one of the optimum separation modes for shotgun proteomic analysis. To identify as many proteins as possible by MS/MS, the improvement on separation efficiency and peak capacity of ,RPLC is indispensable. Although the increase in column length is one of the effective solutions, the preparation of a long microcolumn is rather difficult due to the high backpressure generated during the packing procedure. In our recent work, through connecting microcolumns of 5, 10, and 15,cm length via unions with minimal dead volume, long microcolumns with length up to 30,cm were obtained, with which 318 proteins were identified from proteins extracted from Escherichia coli by ,RPLC-ESI MS/MS, and similar distributions of Mw and pI were found with single and various coupled microcolumns. Furthermore, by using MS/MS with improved sensitivity, with such a serially coupled 30,cm long microcolumn, 1692 proteins were identified within 7,h from rat brain tissue, with false positive rate (FPR) <1%. All these results demonstrated that serially couple microcolumns might be of great promising to improve the separation capacity of ,RPLC in shotgun proteomic analysis. [source]


Fast track to a phosphoprotein sketch , MALDI-TOF characterization of TLC-based tryptic phosphopeptide maps at femtomolar detection sensitivity

PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 21 2006
Vitaly Kochin
Abstract Tryptic phosphopeptide mapping by TLC on microcrystalline cellulose has been a convenient method to get a fast and highly reproducible overview of the number of phosphopeptides present in any given 32P-labeled phosphoprotein. This method also provides an immediate presentation of the relative phosphorylation stoichiometry between individual phosphopeptides. However, so far, traditional tryptic phosphopeptide maps have not been useful for phosphoproteomics applications, as the S/N has been very poor, due to the large number of quenching substances and contaminants present on cellulose plates. In this study, we present a rapid and easy method for phosphopeptides identification from 2-D phosphopeptide maps (2-D-PPMs). We obtain improved sensitivity (femtomole levels) upon MALDI-TOF MS analysis of phosphopeptides extracted from 2-D-PPMs. Using this approach we could confidently characterize the major phosphorylation sites of in,vivo and in,vitro32P-labeled proteins. [source]


Development of a targeted adductomic method for the determination of polycyclic aromatic hydrocarbon DNA adducts using online column-switching liquid chromatography/tandem mass spectrometry

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 16 2010
Rajinder Singh
Human exposure to polycyclic aromatic hydrocarbons (PAHs) from sources such as industrial or urban air pollution, tobacco smoke and cooked food is not confined to a single compound, but instead to mixtures of different PAHs. The interaction of different PAHs may lead to additive, synergistic or antagonistic effects in terms of DNA adduct formation and carcinogenic activity resulting from changes in metabolic activation to reactive intermediates and DNA repair. The development of a targeted DNA adductomic approach using liquid chromatography/tandem mass spectrometry (LC/MS/MS) incorporating software-based peak picking and integration for the assessment of exposure to mixtures of PAHs is described. For method development PAH-modified DNA samples were obtained by reaction of the anti- dihydrodiol epoxide metabolites of benzo[a]pyrene, benzo[b]fluoranthene, dibenzo[a,l]pyrene (DB[a,l]P) and dibenz[a,h]anthracene with calf thymus DNA in vitro and enzymatically hydrolysed to 2,-deoxynucleosides. Positive LC/electrospray ionisation (ESI)-MS/MS collision-induced dissociation product ion spectra data showed that the majority of adducts displayed a common fragmentation for the neutral loss of 116 u (2,-deoxyribose) resulting in a major product ion derived from the adducted base. The exception was the DB[a,l]P dihydrodiol epoxide adduct of 2,-deoxyadenosine which resulted in major product ions derived from the PAH moiety being detected. Specific detection of mixtures of PAH-adducted 2,-deoxynucleosides was achieved using online column-switching LC/MS/MS in conjunction with selected reaction monitoring (SRM) of the [M+H]+ to [M+H,116]+ transition plus product ions derived from the PAH moiety for improved sensitivity of detection and a comparison was made to detection by constant neutral loss scanning. In conclusion, different PAH DNA adducts were detected by employing SRM [M+H,116]+ transitions or constant neutral loss scanning. However, for improved sensitivity of detection optimised SRM transitions relating to the PAH moiety product ions are required for certain PAH DNA adducts for the development of targeted DNA adductomic methods. Copyright © 2010 John Wiley & Sons, Ltd. [source]


A semi-automated solid-phase extraction liquid chromatography/tandem mass spectrometry method for the analysis of tetrahydrocannabinol and metabolites in whole blood,

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 17 2009
Eshwar Jagerdeo
Marijuana is one of the most commonly abused illicit substances in the USA, making cannabinoids important to detect in clinical and forensic toxicology laboratories. Historically, cannabinoids in biological fluids have been derivatized and analyzed by gas chromatography/mass spectrometry (GC/MS). There has been a gradual shift in many laboratories towards liquid chromatography/mass spectrometry (LC/MS) for this analysis due to its improved sensitivity and reduced sample preparation compared with GC/MS procedures. This paper reports a validated method for the analysis of ,9 -tetrahydrocannabinol (THC) and its two main metabolites, 11-nor-9-carboxy-,9 -tetrahydrocannabinol (THC-COOH) and 11-hydroxy-,9 -tetrahydrocannabinol (THC-OH), in whole blood samples. The method has also been validated for cannabinol (CBD) and cannabidiol (CDN), two cannabinoids that were shown not to interfere with the method. This method has been successfully applied to samples both from living people and from deceased individuals obtained during autopsy. This method utilizes online solid-phase extraction (SPE) with LC/MS. Pretreatment of samples involves protein precipitation, sample concentration, ultracentrifugation, and reconstitution. The online SPE procedure was developed using Hysphere C8-EC sorbent. A chromatographic gradient with an Xterra MS C18 column was used for the separation. Four multiple-reaction monitoring (MRM) transitions were monitored for each analyte and internal standard. Linearity generally fell between 2 and 200,ng/mL. The limits of detection (LODs) ranged from 0.5 to 3,ng/mL and the limits of quantitation (LOQs) ranged from 2 to 8,ng/mL. The bias and imprecision were determined using a simple analysis of variance (ANOVA: single factor). The results demonstrate bias as <7%, and imprecision as <9%, for all components at each quantity control level. Published in 2009 by John Wiley & Sons, Ltd. [source]


The Influence of Knowledge of Mammography Findings on the Accuracy of Breast Ultrasound in Symptomatic Women

THE BREAST JOURNAL, Issue 3 2005
FAFPHM, FASBP, Nehmat Houssami MBBS
Abstract: Breast ultrasound is generally interpreted with knowledge of the mammographic examination. This study examined the influence of knowledge of mammography findings on the accuracy of ultrasound in women with breast symptoms. Subjects were sampled from all women 25,55 years of age consecutively attending a breast clinic. This included all 240 women shown to have breast cancer and 240 age-matched women shown not to have cancer. Ultrasound films were prospectively reviewed and reported by two radiologists independent of each other and in a blinded manner. A two-phase design was used. In the first phase, the radiologists provided an opinion on the ultrasound films. In the second phase, the ultrasound films were reread with consideration of the corresponding mammographic examination. The accuracy of reading the ultrasound with and without knowledge of the findings on mammography was compared using sensitivity and specificity, and receiver operating characteristics (ROC) curves. Reporting the ultrasound with knowledge of mammography (compared to without mammography) improved sensitivity and reduced specificity for both radiologists. For one reader, sensitivity increased from 77.5% to 86.7% (p = 0.0002) and specificity decreased from 89.7% to 85.4% (p = 0.04). For the other reader, sensitivity increased from 81.3% to 87.5% (p = 0.0023) and specificity decreased from 87.1% to 85.0% (p = 0.27). ROC curves for both radiologists showed that reporting ultrasound with knowledge of mammography resulted in small (about 3%), but significant improvement in the area under the ROC curve. Our study indicates that knowledge of the findings of mammography improves the interpretation of breast ultrasound in symptomatic women., [source]


Anti,cyclic citrullinated peptide testing for the diagnosis of rheumatoid arthritis and the quest for improved sensitivity and predictive value

ARTHRITIS & RHEUMATISM, Issue 8 2009
Marc C. Levesque
First page of article [source]


A new index of access to primary care services in rural areas

AUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 5 2009
Matthew R. McGrail
Abstract Objective: To outline a new index of access to primary care services in rural areas that has been specifically designed to overcome weaknesses of using existing geographical classifications. Methods: Access was measured by four key dimensions of availability, proximity, health needs and mobility. Population data were obtained through the national census and primary care service data were obtained through the Medical Directory of Australia. All data were calculated at the smallest feasible geographical unit (collection districts). The index of access was measured using a modified two-step floating catchment area (2SFCA) method, which incorporates two necessary additional spatial functions (distance-decay and capping) and two additional non-spatial dimensions (health needs and mobility). Results: An improved index of access, specifically designed to better capture access to primary care in rural areas, is achieved. These improvements come from: 1) incorporation of actual health service data in the index; 2) methodological improvements to existing access measures, which enable both proximity to be differentiated within catchments and the use of varying catchment sizes; and 3) improved sensitivity to small-area variations. Conclusion: Despite their recognised weaknesses, the Australian government uses broad geographical classifications as proxy measures of access to underpin significant rural health funding programs. This new index of access could provide a more equitable means for resource allocation. Implications: Significant government funding, aimed at improving health service access inequities in rural areas, could be better targeted by underpinning programs with our improved access measure. [source]


A randomised comparison of SurePath liquid-based cytology and conventional smear cytology in a colposcopy clinic setting

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 11 2008
PH Sykes
Objective, The objective of this study was to compare the sensitivity of cervical cytology using conventional smears and SurePath liquid-based cytology (LBC). Design, Prospective randomised evaluation of diagnostic test. Setting, A single institution colposcopy clinic. Population, Women attending first visit colposcopy appointments were offered entry into the study. Methods, Cervical cytology samples from 913 women of age 16,75 years were randomly processed as SurePath LBC or conventional smears. Conventional smears were taken for 453 women and a SurePath LBC taken for 451 women. Cytology results were correlated with colposcopic findings and histology from colposcopic biopsies, treatment and follow up. Main outcome measures, To compare the sensitivity of SurePath LBC and conventional smears for histologically proven abnormality. Other outcome measures include a comparison of their sensitivity for high-grade abnormalities and their satisfactory rate. Results, Accounting for all randomised samples, there was a trend towards improved sensitivity for SurePath LBC (79.1 versus 73.7%, P = 0.1). However, excluding unsatisfactory cytology (and samples not taken) eliminated this trend; the sensitivity for both LBC and conventional smears for any epithelial abnormality was 81%. With a threshold of atypical squamous cells of uncertain significance (ASC-US), both SurePath LBC and conventional smears had a sensitivity of 92% for high-grade lesions. SurePath LBC was less likely to be reported as unsatisfactory (2.7 versus 9.1%, P < 0.0001). Conclusions, In this context, with a threshold of ASC-US, both SurePath LBC and conventional smears offer high sensitivity for the detection of CIN2/3, but SurePath LBC is less likely to be reported as unsatisfactory. [source]